LSD1_KDM1: LSD1 (Lysine specific demethylase1) was the founding member of a second class of enzymes that directly reverse histone H3K4 or H3K9 modifications by an oxidative demethylation reaction in which flavin is a cofactor. Full enzymatic activity of LSD1 requires its association with other proteins, such as the CoREST (restin corepressor) complex, indicating that regulatory subunits can have a role in modulating demethylase activity. (1)